recognizing alusil

[bentvalves]

Can alusil be applied to a cast iron sleeve, or like nikasil is it only applied to an aluminum bore?

03 Lamborghini Murcialago. Cylinder liners have a dull grey appearance to them and I'm at a bit of a standstill until I determine what I'm working with.

please advise fellow speed talkers.

[bentvalves]

from what I can find, it is being applied to aluminum only.

[MotionMachine]

Alusil is not applied, the parent material is a high silicon content aluminum. It's a special process to hone them, I did a Youtube video showing how I do BMW V8's, using a profilometer to ensure that each step arrives at the right Ra value before moving on to the next step. I'll try to attach the video on this post, never done it on this laptop.
Oh, yeah, shortly into the video I say nikasil, but I meant to say alusil. Nikasil is a difffeent video.

[bentvalves]

Alusil is not applied, the parent material is a high silicon content aluminum. It's a special process to hone them, I did a Youtube video showing how I do BMW V8's, using a profilometer to ensure that each step arrives at the right Ra value before moving on to the next step. I'll try to attach the video on this post, never done it on this laptop.
Oh, yeah, shortly into the video I say nikasil, but I meant to say alusil. Nikasil is a difffeent video.

these are iron liners in an alloy block.

whatever they are made of or treated with, they are diamond like hard as my stones aren't cutting.

[ptuomov]

Alusil is not applied, the parent material is a high silicon content aluminum. It's a special process to hone them, I did a Youtube video showing how I do BMW V8's, using a profilometer to ensure that each step arrives at the right Ra value before moving on to the next step. I'll try to attach the video on this post, never done it on this laptop.
Oh, yeah, shortly into the video I say nikasil, but I meant to say alusil. Nikasil is a difffeent video.

these are iron liners in an alloy block.

whatever they are made of or treated with, they are diamond like hard as my stones aren't cutting.

I believe that nikasil / nicom can be used to plate steel, iron, or aluminum liners. It is really hard.

Alusil is aluminum only, high silicon at that, Reynolds 390. The process amounts to etching away some part of the alloy material and leaving the very hard silicon exposed as the surface. The problem with alusil is that it requires coated pistons, bare aluminum pistons don't last well on alusil, at least not on old-school alusil. Iron coating was the way to go back in the day. Ferrocoat is the best, but Ferrostan also seems to work. A lot of problems with Ferroprint coating in old Porsche engines.

[bentvalves]

If I had to wager a bet, these bores are DLC treated.

It is like trying to hone glass.

[bentvalves]

double post

[ptuomov]

If I had to wager a bet, these bores are DLC treated.

It is like trying to hone glass.

That’s what Nikasil is like.

[bentvalves]

so I guess nikasil can be applied to iron blocks and sleeves, something I was not aware of. This coming from total-seal and ptuomov.

nikasil has a distinct bright appearance to it however, this looks to be DLC. Diamond like carbon coating which google is telling me has been applied to cylinder bores in industry for many years.

[ptuomov]

so I guess nikasil can be applied to iron blocks and sleeves, something I was not aware of. This coming from total-seal and ptuomov.

nikasil has a distinct bright appearance to it however, this looks to be DLC. Diamond like carbon coating which google is telling me has been applied to cylinder bores in industry for many years.

Nikasil looks different depending on the underlying liner material.

I would bet that the VW/Lambo liner is Nikasil plated.

[bentvalves]

correct the sleeves are indeed nikasil.

thank you mate.

[MotionMachine]

If you are just doing a freshen on those liners, BRM makes flex hones specifically for nikasil. I have one app that I use one on and it does give the correct finish.

[ptuomov]

If you are just doing a freshen on those liners, BRM makes flex hones specifically for nikasil. I have one app that I use one on and it does give the correct finish.

Opinions vary on whether anything needs to be done or should be done to Nikasil bores when pistons and/or rings are replaced. Some say do nothing.
What's your view? My view is that the material is so hard that just flex honing it with usual hone does nothing productive. What does that specifically Nikasil designed hone you mention do?

When I was a kid, there was a small engine with a melted piston that needed to be hammered out of the cylinder. After hammering the piston remnants out with a wood block and a hammer, we couldn't see any marks whatsoever on the Nikasil bore. We run it with a new piston assembly and couldn't tell the difference from new. That said, we couldn't find our a$$es with our too hands and assembled everything on a sand driveway, only one of which conditions has improved since then... and it was not a Lamborghini Murcielago we were working on.

[ptuomov]

Alusil is not applied, the parent material is a high silicon content aluminum. It's a special process to hone them, I did a Youtube video showing how I do BMW V8's, using a profilometer to ensure that each step arrives at the right Ra value before moving on to the next step. I'll try to attach the video on this post, never done it on this laptop.
Oh, yeah, shortly into the video I say nikasil, but I meant to say alusil. Nikasil is a difffeent video.

Question about that BMW V8. Is it an open deck block? If it’s an open deck block, have you found a large benefit from the deck plate? When you torque the heads and the main girdle/caps, does the bore end up much more round if you processed it with the deck plate compared to without the deck plate?

[pdq67]

What is the final honing fluid that is used to hone high silicon cylinders.

I read where it etches away some of the aluminum so the silicon stands proud. Then the silicon has to be knocked down smooth to work right.

pdq67